In conventional magnetic force impulse generator wherein the discharge current of a capacitance is applied to a coil member through a switching device, such as thyristor, the coil member and capacitance inevitably form a series resonant circuit to generate a vibration current. The negative voltage of the charge current, however, is still in the capacitance since such switching device passes a current for positive polarity of the current. In the next charge of the capacitance, a high rush current and a large quantity of electricity are required to cancel the negative voltage in order to charge the capacitance to a positive level.